Line data Source code
1 : // SPDX-License-Identifier: GPL-2.0
2 : /*
3 : * kernel/lockdep_proc.c
4 : *
5 : * Runtime locking correctness validator
6 : *
7 : * Started by Ingo Molnar:
8 : *
9 : * Copyright (C) 2006,2007 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
10 : * Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra
11 : *
12 : * Code for /proc/lockdep and /proc/lockdep_stats:
13 : *
14 : */
15 : #include <linux/export.h>
16 : #include <linux/proc_fs.h>
17 : #include <linux/seq_file.h>
18 : #include <linux/kallsyms.h>
19 : #include <linux/debug_locks.h>
20 : #include <linux/vmalloc.h>
21 : #include <linux/sort.h>
22 : #include <linux/uaccess.h>
23 : #include <asm/div64.h>
24 :
25 : #include "lockdep_internals.h"
26 :
27 0 : static void *l_next(struct seq_file *m, void *v, loff_t *pos)
28 : {
29 0 : return seq_list_next(v, &all_lock_classes, pos);
30 : }
31 :
32 0 : static void *l_start(struct seq_file *m, loff_t *pos)
33 : {
34 0 : return seq_list_start_head(&all_lock_classes, *pos);
35 : }
36 :
37 0 : static void l_stop(struct seq_file *m, void *v)
38 : {
39 0 : }
40 :
41 0 : static void print_name(struct seq_file *m, struct lock_class *class)
42 : {
43 0 : char str[KSYM_NAME_LEN];
44 0 : const char *name = class->name;
45 :
46 0 : if (!name) {
47 0 : name = __get_key_name(class->key, str);
48 0 : seq_printf(m, "%s", name);
49 : } else{
50 0 : seq_printf(m, "%s", name);
51 0 : if (class->name_version > 1)
52 0 : seq_printf(m, "#%d", class->name_version);
53 0 : if (class->subclass)
54 0 : seq_printf(m, "/%d", class->subclass);
55 : }
56 0 : }
57 :
58 0 : static int l_show(struct seq_file *m, void *v)
59 : {
60 0 : struct lock_class *class = list_entry(v, struct lock_class, lock_entry);
61 0 : struct lock_list *entry;
62 0 : char usage[LOCK_USAGE_CHARS];
63 :
64 0 : if (v == &all_lock_classes) {
65 0 : seq_printf(m, "all lock classes:\n");
66 0 : return 0;
67 : }
68 :
69 0 : seq_printf(m, "%p", class->key);
70 : #ifdef CONFIG_DEBUG_LOCKDEP
71 0 : seq_printf(m, " OPS:%8ld", debug_class_ops_read(class));
72 : #endif
73 : #ifdef CONFIG_PROVE_LOCKING
74 0 : seq_printf(m, " FD:%5ld", lockdep_count_forward_deps(class));
75 0 : seq_printf(m, " BD:%5ld", lockdep_count_backward_deps(class));
76 : #endif
77 :
78 0 : get_usage_chars(class, usage);
79 0 : seq_printf(m, " %s", usage);
80 :
81 0 : seq_printf(m, ": ");
82 0 : print_name(m, class);
83 0 : seq_puts(m, "\n");
84 :
85 0 : list_for_each_entry(entry, &class->locks_after, entry) {
86 0 : if (entry->distance == 1) {
87 0 : seq_printf(m, " -> [%p] ", entry->class->key);
88 0 : print_name(m, entry->class);
89 0 : seq_puts(m, "\n");
90 : }
91 : }
92 0 : seq_puts(m, "\n");
93 :
94 0 : return 0;
95 : }
96 :
97 : static const struct seq_operations lockdep_ops = {
98 : .start = l_start,
99 : .next = l_next,
100 : .stop = l_stop,
101 : .show = l_show,
102 : };
103 :
104 : #ifdef CONFIG_PROVE_LOCKING
105 0 : static void *lc_start(struct seq_file *m, loff_t *pos)
106 : {
107 0 : if (*pos < 0)
108 : return NULL;
109 :
110 0 : if (*pos == 0)
111 : return SEQ_START_TOKEN;
112 :
113 0 : return lock_chains + (*pos - 1);
114 : }
115 :
116 0 : static void *lc_next(struct seq_file *m, void *v, loff_t *pos)
117 : {
118 0 : *pos = lockdep_next_lockchain(*pos - 1) + 1;
119 0 : return lc_start(m, pos);
120 : }
121 :
122 0 : static void lc_stop(struct seq_file *m, void *v)
123 : {
124 0 : }
125 :
126 0 : static int lc_show(struct seq_file *m, void *v)
127 : {
128 0 : struct lock_chain *chain = v;
129 0 : struct lock_class *class;
130 0 : int i;
131 0 : static const char * const irq_strs[] = {
132 : [0] = "0",
133 : [LOCK_CHAIN_HARDIRQ_CONTEXT] = "hardirq",
134 : [LOCK_CHAIN_SOFTIRQ_CONTEXT] = "softirq",
135 : [LOCK_CHAIN_SOFTIRQ_CONTEXT|
136 : LOCK_CHAIN_HARDIRQ_CONTEXT] = "hardirq|softirq",
137 : };
138 :
139 0 : if (v == SEQ_START_TOKEN) {
140 0 : if (!nr_free_chain_hlocks)
141 0 : seq_printf(m, "(buggered) ");
142 0 : seq_printf(m, "all lock chains:\n");
143 0 : return 0;
144 : }
145 :
146 0 : seq_printf(m, "irq_context: %s\n", irq_strs[chain->irq_context]);
147 :
148 0 : for (i = 0; i < chain->depth; i++) {
149 0 : class = lock_chain_get_class(chain, i);
150 0 : if (!class->key)
151 0 : continue;
152 :
153 0 : seq_printf(m, "[%p] ", class->key);
154 0 : print_name(m, class);
155 0 : seq_puts(m, "\n");
156 : }
157 0 : seq_puts(m, "\n");
158 :
159 0 : return 0;
160 : }
161 :
162 : static const struct seq_operations lockdep_chains_ops = {
163 : .start = lc_start,
164 : .next = lc_next,
165 : .stop = lc_stop,
166 : .show = lc_show,
167 : };
168 : #endif /* CONFIG_PROVE_LOCKING */
169 :
170 0 : static void lockdep_stats_debug_show(struct seq_file *m)
171 : {
172 : #ifdef CONFIG_DEBUG_LOCKDEP
173 0 : unsigned long long hi1 = debug_atomic_read(hardirqs_on_events),
174 0 : hi2 = debug_atomic_read(hardirqs_off_events),
175 0 : hr1 = debug_atomic_read(redundant_hardirqs_on),
176 0 : hr2 = debug_atomic_read(redundant_hardirqs_off),
177 0 : si1 = debug_atomic_read(softirqs_on_events),
178 0 : si2 = debug_atomic_read(softirqs_off_events),
179 0 : sr1 = debug_atomic_read(redundant_softirqs_on),
180 0 : sr2 = debug_atomic_read(redundant_softirqs_off);
181 :
182 0 : seq_printf(m, " chain lookup misses: %11llu\n",
183 0 : debug_atomic_read(chain_lookup_misses));
184 0 : seq_printf(m, " chain lookup hits: %11llu\n",
185 0 : debug_atomic_read(chain_lookup_hits));
186 0 : seq_printf(m, " cyclic checks: %11llu\n",
187 0 : debug_atomic_read(nr_cyclic_checks));
188 0 : seq_printf(m, " redundant checks: %11llu\n",
189 0 : debug_atomic_read(nr_redundant_checks));
190 0 : seq_printf(m, " redundant links: %11llu\n",
191 0 : debug_atomic_read(nr_redundant));
192 0 : seq_printf(m, " find-mask forwards checks: %11llu\n",
193 0 : debug_atomic_read(nr_find_usage_forwards_checks));
194 0 : seq_printf(m, " find-mask backwards checks: %11llu\n",
195 0 : debug_atomic_read(nr_find_usage_backwards_checks));
196 :
197 0 : seq_printf(m, " hardirq on events: %11llu\n", hi1);
198 0 : seq_printf(m, " hardirq off events: %11llu\n", hi2);
199 0 : seq_printf(m, " redundant hardirq ons: %11llu\n", hr1);
200 0 : seq_printf(m, " redundant hardirq offs: %11llu\n", hr2);
201 0 : seq_printf(m, " softirq on events: %11llu\n", si1);
202 0 : seq_printf(m, " softirq off events: %11llu\n", si2);
203 0 : seq_printf(m, " redundant softirq ons: %11llu\n", sr1);
204 0 : seq_printf(m, " redundant softirq offs: %11llu\n", sr2);
205 : #endif
206 0 : }
207 :
208 0 : static int lockdep_stats_show(struct seq_file *m, void *v)
209 : {
210 0 : unsigned long nr_unused = 0, nr_uncategorized = 0,
211 0 : nr_irq_safe = 0, nr_irq_unsafe = 0,
212 0 : nr_softirq_safe = 0, nr_softirq_unsafe = 0,
213 0 : nr_hardirq_safe = 0, nr_hardirq_unsafe = 0,
214 0 : nr_irq_read_safe = 0, nr_irq_read_unsafe = 0,
215 0 : nr_softirq_read_safe = 0, nr_softirq_read_unsafe = 0,
216 0 : nr_hardirq_read_safe = 0, nr_hardirq_read_unsafe = 0,
217 0 : sum_forward_deps = 0;
218 :
219 : #ifdef CONFIG_PROVE_LOCKING
220 0 : struct lock_class *class;
221 :
222 0 : list_for_each_entry(class, &all_lock_classes, lock_entry) {
223 :
224 0 : if (class->usage_mask == 0)
225 0 : nr_unused++;
226 0 : if (class->usage_mask == LOCKF_USED)
227 0 : nr_uncategorized++;
228 0 : if (class->usage_mask & LOCKF_USED_IN_IRQ)
229 0 : nr_irq_safe++;
230 0 : if (class->usage_mask & LOCKF_ENABLED_IRQ)
231 0 : nr_irq_unsafe++;
232 0 : if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ)
233 0 : nr_softirq_safe++;
234 0 : if (class->usage_mask & LOCKF_ENABLED_SOFTIRQ)
235 0 : nr_softirq_unsafe++;
236 0 : if (class->usage_mask & LOCKF_USED_IN_HARDIRQ)
237 0 : nr_hardirq_safe++;
238 0 : if (class->usage_mask & LOCKF_ENABLED_HARDIRQ)
239 0 : nr_hardirq_unsafe++;
240 0 : if (class->usage_mask & LOCKF_USED_IN_IRQ_READ)
241 0 : nr_irq_read_safe++;
242 0 : if (class->usage_mask & LOCKF_ENABLED_IRQ_READ)
243 0 : nr_irq_read_unsafe++;
244 0 : if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ_READ)
245 0 : nr_softirq_read_safe++;
246 0 : if (class->usage_mask & LOCKF_ENABLED_SOFTIRQ_READ)
247 0 : nr_softirq_read_unsafe++;
248 0 : if (class->usage_mask & LOCKF_USED_IN_HARDIRQ_READ)
249 0 : nr_hardirq_read_safe++;
250 0 : if (class->usage_mask & LOCKF_ENABLED_HARDIRQ_READ)
251 0 : nr_hardirq_read_unsafe++;
252 :
253 0 : sum_forward_deps += lockdep_count_forward_deps(class);
254 : }
255 : #ifdef CONFIG_DEBUG_LOCKDEP
256 0 : DEBUG_LOCKS_WARN_ON(debug_atomic_read(nr_unused_locks) != nr_unused);
257 : #endif
258 :
259 : #endif
260 0 : seq_printf(m, " lock-classes: %11lu [max: %lu]\n",
261 : nr_lock_classes, MAX_LOCKDEP_KEYS);
262 0 : seq_printf(m, " direct dependencies: %11lu [max: %lu]\n",
263 : nr_list_entries, MAX_LOCKDEP_ENTRIES);
264 0 : seq_printf(m, " indirect dependencies: %11lu\n",
265 : sum_forward_deps);
266 :
267 : /*
268 : * Total number of dependencies:
269 : *
270 : * All irq-safe locks may nest inside irq-unsafe locks,
271 : * plus all the other known dependencies:
272 : */
273 0 : seq_printf(m, " all direct dependencies: %11lu\n",
274 0 : nr_irq_unsafe * nr_irq_safe +
275 0 : nr_hardirq_unsafe * nr_hardirq_safe +
276 : nr_list_entries);
277 :
278 : #ifdef CONFIG_PROVE_LOCKING
279 0 : seq_printf(m, " dependency chains: %11lu [max: %lu]\n",
280 : lock_chain_count(), MAX_LOCKDEP_CHAINS);
281 0 : seq_printf(m, " dependency chain hlocks used: %11lu [max: %lu]\n",
282 : MAX_LOCKDEP_CHAIN_HLOCKS -
283 0 : (nr_free_chain_hlocks + nr_lost_chain_hlocks),
284 : MAX_LOCKDEP_CHAIN_HLOCKS);
285 0 : seq_printf(m, " dependency chain hlocks lost: %11u\n",
286 : nr_lost_chain_hlocks);
287 : #endif
288 :
289 : #ifdef CONFIG_TRACE_IRQFLAGS
290 0 : seq_printf(m, " in-hardirq chains: %11u\n",
291 : nr_hardirq_chains);
292 0 : seq_printf(m, " in-softirq chains: %11u\n",
293 : nr_softirq_chains);
294 : #endif
295 0 : seq_printf(m, " in-process chains: %11u\n",
296 : nr_process_chains);
297 0 : seq_printf(m, " stack-trace entries: %11lu [max: %lu]\n",
298 : nr_stack_trace_entries, MAX_STACK_TRACE_ENTRIES);
299 : #if defined(CONFIG_TRACE_IRQFLAGS) && defined(CONFIG_PROVE_LOCKING)
300 0 : seq_printf(m, " number of stack traces: %11llu\n",
301 : lockdep_stack_trace_count());
302 0 : seq_printf(m, " number of stack hash chains: %11llu\n",
303 : lockdep_stack_hash_count());
304 : #endif
305 0 : seq_printf(m, " combined max dependencies: %11u\n",
306 0 : (nr_hardirq_chains + 1) *
307 0 : (nr_softirq_chains + 1) *
308 0 : (nr_process_chains + 1)
309 : );
310 0 : seq_printf(m, " hardirq-safe locks: %11lu\n",
311 : nr_hardirq_safe);
312 0 : seq_printf(m, " hardirq-unsafe locks: %11lu\n",
313 : nr_hardirq_unsafe);
314 0 : seq_printf(m, " softirq-safe locks: %11lu\n",
315 : nr_softirq_safe);
316 0 : seq_printf(m, " softirq-unsafe locks: %11lu\n",
317 : nr_softirq_unsafe);
318 0 : seq_printf(m, " irq-safe locks: %11lu\n",
319 : nr_irq_safe);
320 0 : seq_printf(m, " irq-unsafe locks: %11lu\n",
321 : nr_irq_unsafe);
322 :
323 0 : seq_printf(m, " hardirq-read-safe locks: %11lu\n",
324 : nr_hardirq_read_safe);
325 0 : seq_printf(m, " hardirq-read-unsafe locks: %11lu\n",
326 : nr_hardirq_read_unsafe);
327 0 : seq_printf(m, " softirq-read-safe locks: %11lu\n",
328 : nr_softirq_read_safe);
329 0 : seq_printf(m, " softirq-read-unsafe locks: %11lu\n",
330 : nr_softirq_read_unsafe);
331 0 : seq_printf(m, " irq-read-safe locks: %11lu\n",
332 : nr_irq_read_safe);
333 0 : seq_printf(m, " irq-read-unsafe locks: %11lu\n",
334 : nr_irq_read_unsafe);
335 :
336 0 : seq_printf(m, " uncategorized locks: %11lu\n",
337 : nr_uncategorized);
338 0 : seq_printf(m, " unused locks: %11lu\n",
339 : nr_unused);
340 0 : seq_printf(m, " max locking depth: %11u\n",
341 : max_lockdep_depth);
342 : #ifdef CONFIG_PROVE_LOCKING
343 0 : seq_printf(m, " max bfs queue depth: %11u\n",
344 : max_bfs_queue_depth);
345 : #endif
346 0 : lockdep_stats_debug_show(m);
347 0 : seq_printf(m, " debug_locks: %11u\n",
348 : debug_locks);
349 :
350 : /*
351 : * Zappped classes and lockdep data buffers reuse statistics.
352 : */
353 0 : seq_puts(m, "\n");
354 0 : seq_printf(m, " zapped classes: %11lu\n",
355 : nr_zapped_classes);
356 : #ifdef CONFIG_PROVE_LOCKING
357 0 : seq_printf(m, " zapped lock chains: %11lu\n",
358 : nr_zapped_lock_chains);
359 0 : seq_printf(m, " large chain blocks: %11u\n",
360 : nr_large_chain_blocks);
361 : #endif
362 0 : return 0;
363 : }
364 :
365 : #ifdef CONFIG_LOCK_STAT
366 :
367 : struct lock_stat_data {
368 : struct lock_class *class;
369 : struct lock_class_stats stats;
370 : };
371 :
372 : struct lock_stat_seq {
373 : struct lock_stat_data *iter_end;
374 : struct lock_stat_data stats[MAX_LOCKDEP_KEYS];
375 : };
376 :
377 : /*
378 : * sort on absolute number of contentions
379 : */
380 : static int lock_stat_cmp(const void *l, const void *r)
381 : {
382 : const struct lock_stat_data *dl = l, *dr = r;
383 : unsigned long nl, nr;
384 :
385 : nl = dl->stats.read_waittime.nr + dl->stats.write_waittime.nr;
386 : nr = dr->stats.read_waittime.nr + dr->stats.write_waittime.nr;
387 :
388 : return nr - nl;
389 : }
390 :
391 : static void seq_line(struct seq_file *m, char c, int offset, int length)
392 : {
393 : int i;
394 :
395 : for (i = 0; i < offset; i++)
396 : seq_puts(m, " ");
397 : for (i = 0; i < length; i++)
398 : seq_printf(m, "%c", c);
399 : seq_puts(m, "\n");
400 : }
401 :
402 : static void snprint_time(char *buf, size_t bufsiz, s64 nr)
403 : {
404 : s64 div;
405 : s32 rem;
406 :
407 : nr += 5; /* for display rounding */
408 : div = div_s64_rem(nr, 1000, &rem);
409 : snprintf(buf, bufsiz, "%lld.%02d", (long long)div, (int)rem/10);
410 : }
411 :
412 : static void seq_time(struct seq_file *m, s64 time)
413 : {
414 : char num[15];
415 :
416 : snprint_time(num, sizeof(num), time);
417 : seq_printf(m, " %14s", num);
418 : }
419 :
420 : static void seq_lock_time(struct seq_file *m, struct lock_time *lt)
421 : {
422 : seq_printf(m, "%14lu", lt->nr);
423 : seq_time(m, lt->min);
424 : seq_time(m, lt->max);
425 : seq_time(m, lt->total);
426 : seq_time(m, lt->nr ? div64_u64(lt->total, lt->nr) : 0);
427 : }
428 :
429 : static void seq_stats(struct seq_file *m, struct lock_stat_data *data)
430 : {
431 : const struct lockdep_subclass_key *ckey;
432 : struct lock_class_stats *stats;
433 : struct lock_class *class;
434 : const char *cname;
435 : int i, namelen;
436 : char name[39];
437 :
438 : class = data->class;
439 : stats = &data->stats;
440 :
441 : namelen = 38;
442 : if (class->name_version > 1)
443 : namelen -= 2; /* XXX truncates versions > 9 */
444 : if (class->subclass)
445 : namelen -= 2;
446 :
447 : rcu_read_lock_sched();
448 : cname = rcu_dereference_sched(class->name);
449 : ckey = rcu_dereference_sched(class->key);
450 :
451 : if (!cname && !ckey) {
452 : rcu_read_unlock_sched();
453 : return;
454 :
455 : } else if (!cname) {
456 : char str[KSYM_NAME_LEN];
457 : const char *key_name;
458 :
459 : key_name = __get_key_name(ckey, str);
460 : snprintf(name, namelen, "%s", key_name);
461 : } else {
462 : snprintf(name, namelen, "%s", cname);
463 : }
464 : rcu_read_unlock_sched();
465 :
466 : namelen = strlen(name);
467 : if (class->name_version > 1) {
468 : snprintf(name+namelen, 3, "#%d", class->name_version);
469 : namelen += 2;
470 : }
471 : if (class->subclass) {
472 : snprintf(name+namelen, 3, "/%d", class->subclass);
473 : namelen += 2;
474 : }
475 :
476 : if (stats->write_holdtime.nr) {
477 : if (stats->read_holdtime.nr)
478 : seq_printf(m, "%38s-W:", name);
479 : else
480 : seq_printf(m, "%40s:", name);
481 :
482 : seq_printf(m, "%14lu ", stats->bounces[bounce_contended_write]);
483 : seq_lock_time(m, &stats->write_waittime);
484 : seq_printf(m, " %14lu ", stats->bounces[bounce_acquired_write]);
485 : seq_lock_time(m, &stats->write_holdtime);
486 : seq_puts(m, "\n");
487 : }
488 :
489 : if (stats->read_holdtime.nr) {
490 : seq_printf(m, "%38s-R:", name);
491 : seq_printf(m, "%14lu ", stats->bounces[bounce_contended_read]);
492 : seq_lock_time(m, &stats->read_waittime);
493 : seq_printf(m, " %14lu ", stats->bounces[bounce_acquired_read]);
494 : seq_lock_time(m, &stats->read_holdtime);
495 : seq_puts(m, "\n");
496 : }
497 :
498 : if (stats->read_waittime.nr + stats->write_waittime.nr == 0)
499 : return;
500 :
501 : if (stats->read_holdtime.nr)
502 : namelen += 2;
503 :
504 : for (i = 0; i < LOCKSTAT_POINTS; i++) {
505 : char ip[32];
506 :
507 : if (class->contention_point[i] == 0)
508 : break;
509 :
510 : if (!i)
511 : seq_line(m, '-', 40-namelen, namelen);
512 :
513 : snprintf(ip, sizeof(ip), "[<%p>]",
514 : (void *)class->contention_point[i]);
515 : seq_printf(m, "%40s %14lu %29s %pS\n",
516 : name, stats->contention_point[i],
517 : ip, (void *)class->contention_point[i]);
518 : }
519 : for (i = 0; i < LOCKSTAT_POINTS; i++) {
520 : char ip[32];
521 :
522 : if (class->contending_point[i] == 0)
523 : break;
524 :
525 : if (!i)
526 : seq_line(m, '-', 40-namelen, namelen);
527 :
528 : snprintf(ip, sizeof(ip), "[<%p>]",
529 : (void *)class->contending_point[i]);
530 : seq_printf(m, "%40s %14lu %29s %pS\n",
531 : name, stats->contending_point[i],
532 : ip, (void *)class->contending_point[i]);
533 : }
534 : if (i) {
535 : seq_puts(m, "\n");
536 : seq_line(m, '.', 0, 40 + 1 + 12 * (14 + 1));
537 : seq_puts(m, "\n");
538 : }
539 : }
540 :
541 : static void seq_header(struct seq_file *m)
542 : {
543 : seq_puts(m, "lock_stat version 0.4\n");
544 :
545 : if (unlikely(!debug_locks))
546 : seq_printf(m, "*WARNING* lock debugging disabled!! - possibly due to a lockdep warning\n");
547 :
548 : seq_line(m, '-', 0, 40 + 1 + 12 * (14 + 1));
549 : seq_printf(m, "%40s %14s %14s %14s %14s %14s %14s %14s %14s %14s %14s "
550 : "%14s %14s\n",
551 : "class name",
552 : "con-bounces",
553 : "contentions",
554 : "waittime-min",
555 : "waittime-max",
556 : "waittime-total",
557 : "waittime-avg",
558 : "acq-bounces",
559 : "acquisitions",
560 : "holdtime-min",
561 : "holdtime-max",
562 : "holdtime-total",
563 : "holdtime-avg");
564 : seq_line(m, '-', 0, 40 + 1 + 12 * (14 + 1));
565 : seq_printf(m, "\n");
566 : }
567 :
568 : static void *ls_start(struct seq_file *m, loff_t *pos)
569 : {
570 : struct lock_stat_seq *data = m->private;
571 : struct lock_stat_data *iter;
572 :
573 : if (*pos == 0)
574 : return SEQ_START_TOKEN;
575 :
576 : iter = data->stats + (*pos - 1);
577 : if (iter >= data->iter_end)
578 : iter = NULL;
579 :
580 : return iter;
581 : }
582 :
583 : static void *ls_next(struct seq_file *m, void *v, loff_t *pos)
584 : {
585 : (*pos)++;
586 : return ls_start(m, pos);
587 : }
588 :
589 : static void ls_stop(struct seq_file *m, void *v)
590 : {
591 : }
592 :
593 : static int ls_show(struct seq_file *m, void *v)
594 : {
595 : if (v == SEQ_START_TOKEN)
596 : seq_header(m);
597 : else
598 : seq_stats(m, v);
599 :
600 : return 0;
601 : }
602 :
603 : static const struct seq_operations lockstat_ops = {
604 : .start = ls_start,
605 : .next = ls_next,
606 : .stop = ls_stop,
607 : .show = ls_show,
608 : };
609 :
610 : static int lock_stat_open(struct inode *inode, struct file *file)
611 : {
612 : int res;
613 : struct lock_class *class;
614 : struct lock_stat_seq *data = vmalloc(sizeof(struct lock_stat_seq));
615 :
616 : if (!data)
617 : return -ENOMEM;
618 :
619 : res = seq_open(file, &lockstat_ops);
620 : if (!res) {
621 : struct lock_stat_data *iter = data->stats;
622 : struct seq_file *m = file->private_data;
623 :
624 : list_for_each_entry(class, &all_lock_classes, lock_entry) {
625 : iter->class = class;
626 : iter->stats = lock_stats(class);
627 : iter++;
628 : }
629 : data->iter_end = iter;
630 :
631 : sort(data->stats, data->iter_end - data->stats,
632 : sizeof(struct lock_stat_data),
633 : lock_stat_cmp, NULL);
634 :
635 : m->private = data;
636 : } else
637 : vfree(data);
638 :
639 : return res;
640 : }
641 :
642 : static ssize_t lock_stat_write(struct file *file, const char __user *buf,
643 : size_t count, loff_t *ppos)
644 : {
645 : struct lock_class *class;
646 : char c;
647 :
648 : if (count) {
649 : if (get_user(c, buf))
650 : return -EFAULT;
651 :
652 : if (c != '0')
653 : return count;
654 :
655 : list_for_each_entry(class, &all_lock_classes, lock_entry)
656 : clear_lock_stats(class);
657 : }
658 : return count;
659 : }
660 :
661 : static int lock_stat_release(struct inode *inode, struct file *file)
662 : {
663 : struct seq_file *seq = file->private_data;
664 :
665 : vfree(seq->private);
666 : return seq_release(inode, file);
667 : }
668 :
669 : static const struct proc_ops lock_stat_proc_ops = {
670 : .proc_open = lock_stat_open,
671 : .proc_write = lock_stat_write,
672 : .proc_read = seq_read,
673 : .proc_lseek = seq_lseek,
674 : .proc_release = lock_stat_release,
675 : };
676 : #endif /* CONFIG_LOCK_STAT */
677 :
678 1 : static int __init lockdep_proc_init(void)
679 : {
680 1 : proc_create_seq("lockdep", S_IRUSR, NULL, &lockdep_ops);
681 : #ifdef CONFIG_PROVE_LOCKING
682 1 : proc_create_seq("lockdep_chains", S_IRUSR, NULL, &lockdep_chains_ops);
683 : #endif
684 1 : proc_create_single("lockdep_stats", S_IRUSR, NULL, lockdep_stats_show);
685 : #ifdef CONFIG_LOCK_STAT
686 : proc_create("lock_stat", S_IRUSR | S_IWUSR, NULL, &lock_stat_proc_ops);
687 : #endif
688 :
689 1 : return 0;
690 : }
691 :
692 : __initcall(lockdep_proc_init);
693 :
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